Device for guiding yarn



Oct. 8, 196s M, KUBOVY ET AL -3,404,523

DEvcE FOR GUIDING YARN Filed Dec. l, 1966 :l ik INVE7'MTOR8 UnitedStates Patent O 3,404,523 DEVICE FOR GUIDING YARN Miloslav Kubovy, DolniDobrouc, Erik Jirasek, Usti nad Orlici, Karel Zavadsky, Hnatnice, andJosef Stary, Usti nad Orlici, Czechoslovakia, assignors to VyzkumnyUstav Bavlnarsky, Usti nad Orlici, Czechoslovakia Filed Dec. 1, 1966,Ser. No. 598,275 Claims priority, application Czechoslovakia, Dec. 1,1965, 7,196/ 65 6 Claims. (Cl. 57-58.89)

ABSTRACT F THE DISCLOSURE A device for guiding yarn which passes fromthe outlet of a rotary spinning chamber to a yarn take-up. The devicecomprises a guide member formed with an elongated yarn-conveying passageand this passage has an intermediate portion of smallest cross sectionand two outward portions located on opposite sides of the intermediateportion. Each of the outward portions has a cross section whichincreases in the direction away from the intermediate portion.

Background of the invention The present invention relates to an improvedyarn guiding device, and more specifically to a device for guiding yarnwhich passes from the outlet of a rotary spinning chamber to a yarntake-up. Still more specilically, the invention relates to such a yarnguiding device for guiding yarn fromthe spinning chamber of an apparatusused in the continuous ringless spinning of fibers.

It is known to feed into rotary spinning chambers a stream ofsubstantially separated fibers which impinge against an innercircumferential surface of the spinning chamber and are depositedthereon in cohesive form as the result of the centrifugal force to whichthey are subjected upon impinging against the wall surface. The spinningchamber is provided with an outlet and the layer which is continuouslybeing deposited on the wall surface is withdrawn through this outlet inform of a yarn. To guide the yarn during its movement out of thespinning chamber and through the outlet thereof it is known to provide adevice known as a funnel which is formed with a passage of substantiallyconstant cross section` through which the yarn passes. However, theseprior-art devices are possessed of certain disadvantages. Firstly, theyarn rubs against the wall surrounding the opening of substantiallyconstant cross section, and secondly, the yarn also rubs against theedge at the inlet end of the yarn guiding passage, that is the end whichcommunicates with the outlet of the spinning chamber. Obviously, in bothcases the yarn is subjected to a certain amount of damage and it neednot be specifically emphasized that this is highly undesirable.Furthermore, the use of these devices with known spinning chambers makesit very difiicult to return the end of the yarn into the spinningchamber if a yarn breakage has occurred and if it is necessary toreprime, that is to reconnect the end of the yarn to the layer which hasformed on the inner circumferential surface of the spinning chamberwall.

All of these are disadvantages which have long made it desirable toprovide improvements in the state of this art. However, suchimprovements heretofore have not existed.

Summary of the invention With the above comments in mind, it is ageneral object of the present invention to overcome the disadvantages ofthe prior art as set forth hereinbefore.

A more specific object of the invention is to provide a device forguiding yarn which passes from the outlet 3,404,523 Patented Oct. 8,1968 of the rotary spinning chamber to a yarn take-up, and such a deviceis not to damage in any way the yarn passing therethrough.

An additional object of the invention is to provide such a device of thetype set forth above which facilitates returning of the yarn end intothe spinning chamber for the purpose of repriming.

In accordance with one feature of our invention we provide a device forguiding yarn which passes from the outlet of the rotary spinning chamberto a yarn take-up. Such device comprising a guide member having anelongated yarn-conveying passage therein. The passage has anintermediate portion of smallest cross section and it further comprisestwo `outward portions which are located on opposite sides of theintermediate portion. Each of the outward portions has a cross sectionwhich increases in the direction away from the intermediate portion.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following description of specificembodiments when read in connection with the accompanying drawings.

Brief description of the drawing The single figure is a somewhatschematic, partially sectioned elevational view of a device inaccordance with the present invention.

Description of the preferred embodiment Discussing now the drawing indetail it will be seen that reference numeral 4 identifies a rotaryspinning chamber which rotates in the direction of the arrow. Thespinning chamber 4 is provided with an internal circumferentialcollecting surface 3 and has an open end which is not identified with aseparate reference numeral but is clearly evident. Spaced from this openend th"e spinning chamber 4 is provided in its circumferential wall witha plurality of orifices 5 and the purpose of these is to set up, duringrotation of the chamber 4, a negative pressure within the chamber 4.

A channel or tube 2 extends into the open end of the chamber 4 and feedsa constant stream 1 of separated bers into the interior of spinningchamber 4 so that these fibers impinge against the collecting surface 3.Under the influence of centrifugal force, to which they are subjectedupon impinging against the collecting surface 3, the fibers of stream 1form a relatively cohesive mass which is withdrawn from the collectingsurface 3 in form of a yarn 6. A withdrawing device, which may consistof two nip rollers 9, one of which may be driven, is provided spacedfrom the outlet of the rotary spinning chamber 4 and downstream of thiswithdrawing device there is provided a yarn take-up, such as bobbin 10onto which the yarn is wound.

In accordance with the invention the yarn is guided out of the open sideof the spinning chamber 4 by a guiding device, namely the funnel 8. Thisfunnel 8 is provided with a draw-off channel 7 extending the entirelength of the funnel and having, as is clearly evident from the drawing,an intermediate portion of smallest cross section and two outwardportions which are located on `opposite sides of the intermediateportion. Each of these outward portions has a cross section whichincreases in the direction away from the intermediate portion as is alsoevident from the drawing. As shown, the yarn 6 being withdrawn from thecollecting surface 3 of the rotary spinning chamber 4 is gentlydeflected by the innermost outward portion of the channel 7, that is theoutward portion which is located at or within the open side of thespinning chamber 4 and which converges in its cross section toward theportion of narrowest cross section. There is no pronounced edge againstwhich the yarn 6 could rub and thereby be damaged, and there is only arelatively small or rather short wall portion over which the yarn 6contacts the wall surrounding the passage 7. Once the yarn has passedthrough the portion of narrowest cross section of the passage 7 itpasses into the other outward portion, that is the one which is locatedfarther spaced from the spinning chamber 4, `and it is evident from thedrawing that there is now no further contact between the yarn 6 and thereceding surface 11 of the wall which bounds that other outward portionof the channel 7.

Clearly, the construction here shown greatly -reduces damage resultingfrom frictional contact between the yarn 6 and the funnel 8 and thuscontributes significantly tofa more efficient handling of the yarn.

However, this is by no means the only advantage of the construction inaccordance with the present invention. As has been pointed out earlier,when the yarn 6 breaks its free end must be returned into the spinningchamber 4 so that it will contact again the collecting surface 3 andthus be linked up or connected to the fibrous mass which is beingwithdrawn therefrom so that the yarn will again be continuous. Thisprocess is known as repriming and the procedure therefore is known inthe art. A detailed discussion of this procedure is therefore notbelieved to be necessary and it might merely be pointed out that thenegative pressure existing in the in-terior of the rotary spinningchamber 4 helps to convey the returning yarn end into the interior ofthe chamber and into contact with the collecting surface 3 thereof. Inaccordance with the present invention the return of the free yarn end 6into the spinning chamber 4 is aided by the fact that 'the outer one ofthe outward portions of channel 7, that is the one which is locatedcloser to the withdrawing device 9, diverges in its cross section in thedirection towards this withdrawing device. This may also be reverselystated by saying that its cross section decreases in the directiontowards the spinning chamber so that the free end of the yarn 6, whensuch free end is being returned into the spinning chamber 4, is thusreliably guided by the converging surfaces 11 into the portion ofnarrowest cross section of the channel 7. From there, and by virtue ofthe fact that the cross section then 4again increases as seen in thedirection of the returning movement of the free yarn end, the yarn willmove along the diverging surface of the inner of the outward portions ofchannel 7 and will thereby be guided gently in the direction towards thecollecting surface 3 for link-up with the fibrous mass forming thereon.This is assisted by the fact that the velocity of the carrier mediumutilized in repriming increases as the cross section of the channel 7decreases, as seen in the direction of the returning movement of the s 4free yarn end, so that the speed of the yarn end is accelerated and theyarn is straightened. Of course, this does not preclude the possibilitythat a suitable priming element or implement be additionally used orsubstituted, but in any case the `advantage inherent in the novelconstruction, both for withdrawing of yarn and for returning of the yarnend for the purpose of repriming, will be clearly obvious. i

It will be understood that each of the elements described above, or twoor more together, may also find a useful application in other types ofyarn guiding devices differing from the types described above.

While the invention has been illustrated and described as embodied in ayarn guiding device, it is not intended to be limited to the detailsshown, since various modifications and structural changes may be madewithout departing in any way from the spirit of the present invention.

What is claimed as new Iand desired to be protected by Letters Patent isset forth in the appended claims:

1. In a spinning device, in combination, a rotary spinning chamberhaving an outlet; and guide means for guiding yarn which passes fromsaid guide means, comprising a guide member having an elongatedyarn-conveying passage therein, said passage having an intermediateportion of smallest cross-section and two outward portions located onopposite sides of said intermediate portion and each having lacross-section which increases in the direction away from saidintermediate portion, one of said outward portions being located in saidspinning chamber and said intermediate portion being located within theconfines of said outlet.

2. A device as defined in claim 1, wherein the crosssection of the otheroutward portion diverges conically.

3. A device as defined in claim 1, wherein the length of said oneoutward portion is considerably less than the length of the otheroutward portion.

4. A device as defined in claim 3, wherein the crosssection of saidother outward portion diverges conically.

5. A device as defined in claim 4, wherein the crosssection of said oneoutward portion diverges at a greater angle than the cross-section ofsaid other outward portion.

6. A device as defined in claim 1, wherein said passage extendssubstantially normal to the direction of rotation of said spinningchamber.

I FOREIGN PATENTS 976,512 11/1964 Great Britain.

ALLEN N. KNOWLES, Primary Examiner.

